Frequency modulation tube with a surrounding magnetic system



y 1969 H.-SARNEZK|\ ETAL 3,444,418

FREQUENCY MODULATION TUBE WITH A SURROUNDING MAGNETIC SYSTEM Filed Aug. 5. 1966 Sheet of 2 ATTYS.

MaLy 13, 1969 I NE ET AL 3,444,418

FREQUENCY MODULATION TUBE WITH A SURROUNDING MAGNETIC SYSTEM Filed Aug. 5, 1966 Sheet ,2 of 2 Fig.2

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United States Patent 3,444,418 FREQUENCY MODULATION TUBE WITH A SURROUNDING MAGNETIC SYSTEM Herbert Sarnezki and Eberhard Ade, Munich, Germany,

assignors to Siemens Aktiengesellschaft, Munich, Germany, a corporation of Germany Filed Aug. 5, 1966, Ser. No. 570,659 Claims priority, application Germany, Aug. 9, 1965,

98,738 Int. Cl. H01j 25/34 US. Cl. 315-3.5 12 Claims ABSTRACT OF THE DISCLOSURE The invention relates to a velocity-modulated tube such as klystrons and traveling wave tubes with a surrounding magnetic system, which permits a changing of the tube by opening the system into mirror symmetrical halves and in which there is rigidly installed at least one high frequency connecting line for the tube.

There are already known permanent magnet systems for the bundled guidance of an electron beam over a relatively great distance, especially for traveling wave tubes, which may be opened into two halves along a plane of symmetry, in order, even with a compact design of the magnetic system, to make it possible without difficulty to change in the system a tube having end portions which are of greater thickness than the middle portion of the tube. In connection with such a separable magnet system it has already been suggested that there can also be installed in the magnet system hollow conductors for coupling and decoupling purposes, such hollow conductors likewise being separably constructed.

It is necessary for the bundled guidance of the electron beam of a velocity-modulated tube in a magnetic system, that the tube be centrally supported in the magnetic system with respect to the magnetic axis of the later. For this purpose prior known magnetic systems, which can be opened up for the tube change, have been provided with special means for centering and fastening the tube, which in a tube change must be released or readjusted. Furthermore, a tube disposed in such a magnetic system must additionally be connected to corresponding high frequency lines, which lines must be initially released before the opening of the magnetic system. This requires a special expenditure in the form of flexible line terminals with special flanged plug connections, the incorporation of which in the system requires a certain amount of space therein. The releasing and reconnection of the cable plug connections, moreover, requires a special expenditure of time in effecting a tube change in the magnetic system.

Underlying the invention is the problem of designing a microwave electron beam tube with a cooperable magnetic system, which can be opened in such a way that changing of the tube in the system can be readily accomplished in a simple manner. For the solution to this problem, in a velocity-modulated tube of the type referred to it is proposed, according to the invention, that the high frequency connecting lines be constructed to simultaneously function as a carrier and centering element for the tube in the magnetic system.

A microwave tube system according to the invention presents the important advantage that in changing the tube in the magnetic system, other than the high frequency connections, no additional connections for the tube attachment have to be released, as the high frequency contacting elements simultaneously provide the means for fastening of the tube. The manual operations necessary for the tube change are thereby simplified, which can be considered equivalent to a reduction of the drop-out time resulting from the tube change. Furthermore if, in contrast to the previously known tube systems with a separable magnetic system, in which for technical reasons of operation the high frequency connecting lines lie in the separation plane of the magnetic system, the high frequency connection lines are aligned in the plug-in direction of the tube and arranged within one of the two halves of the magnet system additional space can be saved within the magnetic system.

Elongated traveling wave tubes, especially those of relatively high power, ordinarily have a high frequency connection terminal at each of the tube ends. In securing tubes of this type, in accordance with the invention, in a separable magnetic system, it is recommended that only one of the two high frequency connection lines, in particular the connection line for the tube output, be made completely rigid, while the second connecting line is slightly movable in the longitudinal direction of the tube, as well as transversely to the tube axis, in order to achieve a compensation of tolerances, and tube expansion.

Traveling wave tubes frequently are provided with coaxial line terminals. In order, in the arrangement of such tubes in a magnetic system according to the invention, to compensate tube tolerances it is proposed, according to further features of the invention, that one of the two high frequency terminals for the tube be assembled in the magnetic system as a movable coaxial line plug connection, in which the outer conductor of a coaxial line mounted in the magnetic system has an annular recess on the face of its free end bounded at one side by .a rim portion composed of resilient lamellae, into which is inserted the outer conductor of a coaxial line section con nected with the tube shell. The inner conductor of such coaxial line section is here constructed as a resilient contact clip which receives the free end of the inner conductor of the coaxial line mounted in the magnetic system.

The invention will be explained in greater detail with the aid of the figures of the drawing, wherein like or corresponding parts are designated by like reference characters, and in which:

FIG. 1 is a schematic, exploded view of a magnetic system and tube structure utilizing the invention;

FIG. 2 is a longitudinal section of a plug connector in accordance with the invention; and

FIG. 3 is a view similar to FIG. 1 of a structure for use with tubes having centrally disposed tube connections.

FIG. 1 illustrates the construction and arrangement according to the invention of a traveling Wave tube with the cooperative magnetic system. Reference numeral 1 designates a schematically represented hollow magnet structure, which is hinged to form two symmetrical halves, permitting it to be opened by movement according to the arrow 2. In one of the two halves of the magnet structure 1 there is rigidly installed, perpendicular to the separation plane of the structure, a high frequency connection line 3, by means of which the high frequency connection with the high frequency output 4 of the tube 5 is established. The high frequency line 3 can be a coaxial line or a hollow conductor. Its position determines the centering of the tube 5 in the magnet structure 1. For this purpose expediently, there is provided on the free end of the high frequency connectiOn line 3 a flange 6 which carries two externally threaded guide studs 7. Cooperable with the guide studs 7 are two guide holes 8 disposed in a flange 9, which is mounted on the output side high frequency connection 4 of the tube and is firmly connected with the shell of tube 5. The end flange 9 is secured to the flange 6 on the connecting line 3 by two internally threaded mounting nuts or knobs 10. The high frequency contacting between the high frequency connection 4 and the connection line 3 can be constructed as a flange contact or a coaxial external contact connection. With flange contacts, the knobs 10 in addition to fixing the tube position, also effect the necessary contact pressure, while in coaxial external contacts the knobs 10 merely fix the tub in position.

The high frequency connection line 11 for the input side high frequency connection 12 of the tube 5 corresponds in basic design to that of the high frequency connection at the tube output. The high frequency connection line 11, however, should be slightly movable according to the double arrow 13, in axial direction of the tube 5, in order to be able to compensate for heat expansion of tube 5 occurring in operation. In flange connections such as are represented in the example of construction illus trated, the adjacent end of the high frequency connection line 11 must also be slightly movable transversely to the tube axis, to compensate for tolerances in the parallelism of the flanges 6 and 9.

As is evident from FIG. 1, a changing of the tube 5 in the magnet structure 1 is a very simple operation. The magnet system is first opened, following which the voltage feed supply means (not represented) and the mounting knobs 10 are loosened. The tube then can immediately be taken out of the magnet structure 1, whereupon a new tube 5 is inserted, in the direction of the arrow 14 along the dot-dash lines 15, on the guide studs 7 and the mounting knobs 10 are screwed onto the studs 7. Thereupon it remains merely necessary to attach the voltage feed supply means and close the magnetic system.

In order to also simplify the connecting of the voltage feed supply means, the tube base 16 with the contacts for the voltage feed supply advantageously is so arranged that it is substantially axially aligned in tube plug-in direction 14. The contacting with the tube base 16 can there be eflected by means of a manually connectable plug. In the magnet structure 1 there is expediently additionally installed the air cooling feed and lead-off connections (not shown) for the collector of the tube 5, in the event the latter is enclosed by an air cooling casing 17, as illustrated.

The high frequency connection lines 3 and 11 can be connected externally of the magnet structure 1 by means of suitable known standard plug connections 18 to a high frequency circuit of the usual type, Which standard plug connections do not have to be released in the tube changing operation. The line connected with the high-frequency connecting line 3 can be rigid, and may, for example, be a rigid coaxial line 19. On the other hand, the connecting line 11 for the tube input expediently utilizes a flexible cable 29, which participates in the possible movements of the connection line 11. If nevertheless there is required a rigid outside line for the tube input, the movement of the connecting line 11 can be compensated for in a known manner, for example, over a so-called carden connecting structure. Such a cardan coaxial structure is then expediently arranged in the magnet structure between the flange 6 and the standard plug connection 18.

In an arrangement according to FIG. 1, there can be provided for the compensation of heat expansion of the tube 5, instead of a flange connection which is slightly movable in two planes, a movable coaxial line plug connection. FIG. 2 illustrates a plug connection suitable for this purpose, disposed between two coaxial lines 21 and 22, in which the line 21 corresponds to the high frequency connection line 11 of FIG. 1 and the line 22 corresponds to the input-side high frequency connection 12 connected with the shell of tube 5. The outer conductor of the coaxial line 21 is provided at its open end face with a recess 23 which is bounded on its inner surface of generation by a series of resilient contact springs or lamellae 25. The free end of the outer conductor of the coaxial line 22, of wedge form in axial cross section, is adapted to be inserted in the recess 23, while the inner conductor, in the form of a resilient contact clip 24, receives the end of the inner conductor of the coaxial line 21. The contact springs 25, which are situated on the inside of the annular recess 23, or springs 25' forming the contact clip 24, provide the desired compensation of operating and manufacturing tolerances of the tube. It should be noted that the coaxial line plug connection illustrated in FIG. 2 is of importance, independently of the present invention, in applications where movements can occur between two coaxial lines to be connected with one another.

FIG. 3 illustrates a further example of construction of the invention and in particular for a velocity-modulated tube 26, in which the high frequency connections are arranged in the middle of the tube and extend parallel to one another outwardly from the tube shell. In this case the corresponding high frequency connection lines in the magnet structure 1 are spatially grouped into a single unit with a single flange 27. At opposite edges of such flange there are disposed, at the tube side thereof, two guide rods 28, on which guide tubes 29, carried by the tube 26, are slidable. The guide rods 28 are each provided with a threaded bore, so that the tube 26 can be secured in its inserted position on the guide rods 28 by means of threaded knobs 30. The two knobs 30 do not, in this case, merely fix the tube in position, but also produce the necessary contact pressure to effect the operative connection of the hollow conductor flange element between the connection installed in the magnet structure and the high frequency connection terminals of the tube 26. On the end flange 31 of tube 26 there are simultaneously accommodated the contact pins 32 for the voltage feed supply cooperable plug sockets 33 being disposed at opposite edges of the flange 27 in the magnet structure 1. In this manner a changing of the tube 26, which may, for example, be a radar receiver tube, becomes extremely simple and requires very small expenditure of time. To make such a tube change it is merely necessary to open the magnetic system and to change the tube, whereupon, by tightening knobs 30 and closing the magnet system the latter is immediately again ready for operation.

The invention is not limited only to the examples of construction illustrated. In particular, instead of guide studs located on the connection lines in the magnet system, other means are utilized for the centering and supporting of the tube in the system. What is of particular importance is the connection between the high frequency connections of the tube and the connection lines installed in the magnet system, in addition to its normal function of the high frequency contacting, simultaneously fulfills the purpose of supporting and centering the tube in the magnetic field Without requiring any further fastening means.

Changes may be made within the scope and spirit of the appended claims which define what is believed to be new and desired to have protected by Letters Patent.

We claim:

1. A velocity-modulated tube with a surrounding magnetic system which can be opened for the changing of the tube, comprising a velocity-modulated tube structure, a magnetic system constructed in the form of two mirrorimage symmetrical halves, at least one high-frequency connection, for the tube, which is rigidly mounted in the magnetic system, said high-frequency connection line being constructed to center, and simultaneously provide support for said tube structure within the magnetic system.

2. A velocity-modulated tube according to claim I having high-frequency connections which are rigidly connected to the tube shell and terminate in free end flange means, and base means on the free end of the cooperable tube carrying and centering connection line in the magnetic system, provided with the means for the centering and supporting of the cooperable end flange means of said tube structure.

3. A velocity-modulated tube according to claim 2, wherein said base means carries at least two guide studs, the cooperable end flange means at the tube side being provided with cooperable guide holes disposed to receive the respective guide studs, and forming said centering and supporting means.

4. A velocity-modulated tube according to claim 3, wherein said guide studs are provided with threads cooperable with threaded fastening elements by means of which the tube structure is secured to the high-frequency connection.

5. A velocity-modulated tube according to claim 4, wherein the base of the tube structure is provided with contacts for the voltage feed connections, which extend in the same direction as said high-frequency connection of the tube shell.

6. A velocity-modulated tube according to claim 5, wherein the contacts for the tube supply voltages are accommodated on the end flange means of such high-frequency connection, and a cooperable plug socket carried by the end of the cooperable high-frequency connection line in the magnetic system.

7. A magnetic system for a velocity-modulated tube, comprising a magnet system of a size to receive such a tube therein, said system being divided into two mirrorimage symmetrical halves, one of said halves containing all the necessary high-frequency connection lines for such a velocity-modulated tube disposed in said magnet system, with such lines extending perpendicularly to the separating plane of the magnet system.

8. A magnet system according to claim 7, for a traveling wave tube with two high-frequency connections remote from one another in longitudinal direction of the tube, wherein one of the two cooperable connection lines of the magnet system is rigidly fixed therein, while the other connection line is slightly movable relative thereto in the longitudinal direction of the tube.

9. A magnet system according to claim 8, wherein the movable connection line is provided with a flexible cable for effecting external connection to a high-frequency line.

10. A magnet system according to claim 9, with a flange contact between the movable connection line and the cooperable high-frequency connection of the tube, wherein the movable connection line is arranged for a slight movement transversely to the tube axis, aes well as in a longitudinal direction of the tube.

11. A magnet system according to claim 7, for a velocity-modulated tube with two high-frequency connections centrally disposed on the tube, wherein the cooperable connection lines of the magnet system are rigidly fixed therein in adjacent relation.

12. A line plug connection for two abutting coaxial line ends, each having an outer conductor and a coaxially disposed inner conductor, in which the outer conductor of one coaxial line is provided with an annular recess in the end face thereof, which is defined at one side thereof by a series of resilient lamellae, into which recess is inserted the free end of the outer conductor of the other coaxial line, which free end is of generally wedge-shape in axial cross section, the free end of the inner conductor of the last-mentioned coaxial line being constructed in the form of a resilient contact clip which receives the adjacent end of the inner conductor of the first-mentioned coaxial line.

References Cited UNITED STATES PATENTS 2,784,339 3/1957 Lindenblad 3 l53.5 3,045,202 7/1962 Shapiro 339-64 3,188,515 6/1965 Kompfner SIS-3.5

HERMAN KARL SAALBACH, Primary Examiner.

PAUL L. GENSLER, Assistant Examiner.

US. Cl. X.R. 

